AN ECOLOGICAL ASSESSMENT OF COUPLED CLIMATE CHANGE AND HUMAN ACTIVITIES ON WETLANDS IN ZHALONG NATURE RESERVE, CHINA

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1 AN ECOLOGICAL ASSESSMENT OF COUPLED CLIMATE CHANGE AND HUMAN ACTIVITIES ON WETLANDS IN ZHALONG NATURE RESERVE, CHINA Yankun Sun * Center for Global Change and Earth Observations, MSU, MI 883, USA, Northeast agricultural university, Harbin 153, China Jiaguo Qi Center for Global Change and Earth Observations, MSU, MI 883, USA Guoping Lei, Hui Zhang Northeast agricultural university, Harbin 153, China Introduction Wetlands are land areas that are periodically flooded or covered with water. It is the presence of water at or near the soil surface for more than a few weeks during the growing season that may help to create many wetland conditions (Lyon, ).The 8-square-mile (,175-km ) Zhalong Nature Reserve (ZNR) is located in the western part of Heilongjiang province of China, bordered by Qiqihar City, Lindian and Dumeng County. It lies in the western part of the Songnen Plain and comprises marshes and lakes in the Wuyuer River watershed, between 6 5 and 7 3 N, and 13 7 and 1 37 E, at 1-16 m above sea level. ZNR is composed of permanent and seasonal freshwater marshes with numerous shallow lakes and ponds and extensive reed beds in the lower drainage basin of the Wuyuer River. Grassland, reed thickets, farmland, and fish farms surround this reserve. Summer is the most humid season, with the average rainfall of 7% of the total annual precipitation. The site receives most rainfall in July, which is also the warmest month in the year. ZNR became a provincial nature reserve in 1979 initiated by Heilongjiang province government, later became a national nature reserve in 1987 by China State Department, and listed in the World Important Wetland Contents in 199 by the United Nations. Being well known for its red-crowned cranes and other kinds of cranes, Zhalong is called as Crane s Country. There are total 15 kinds of crane in the world, ZNR has 6 of them. The 1/6 of the total world-wide red-crowned crane population comes to Zhalong Reserve (Zou, 3). * Corresponding author address: Yankun Sun, Center for Global Change and Earth Observations, MSU, MI 883, USA; Northeast agricultural university, Harbin 153, China; sunyanku@msu.edu Zhalong Nature Reserve is a world important wetland which is well known for its red-crowned cranes. However, in recent years, Zhalong s wetlands have been facing increasingly threats from both intensified human exploitation and recent climate change. Using meteorological observations over the past 5 years, remote sensing images over the past 3 years, field surveys, and geospatial technologies, we conducted an analysis to improve our understanding of the dynamics of wetlands as a function of socioeconomic factors along with climate drivers. In this paper, we attempted to address the following coupled issues: 1) recent climate trend analysis in the Zhalong area, ) consequences of increasing human activities and changes in policies coupled with climate change, and 3) recommendation for improved protection of ZNR. Climate trend Using meteorological observations from the closest weather station, Lindian, over the past 5 years, we analyzed the climate trends of ZNR. Figs.1, and 3 indicate that, over the past years, the annual mean air temperature in the reserve rose significantly; there were only 5 years when the mean annual temperatures were above its 5 year mean (3. C) in the prior 3 years ( ), however, in the recent 18 years (1988-5), all the temperatures were above the mean values. The annual mean temperature increased from its 5 year mean by.11,.85 and 1. C for the period of 198s, 199s and s, respectively, reflecting a 3.5%, 6.6% and 31.3% increases. It is shown from the coefficients of variation (CV) in Table 1 that the temperature in the falls and springs increased sharply with large fluctuations, while the winter temperature increased a little and no change was observed for the summer period. The annual mean minimum

2 temperature increased significantly, but the maximum values changed little. Fig. showed that the annual mean precipitation of the recent past 11 years (99mm) decreased, as there were only two in the 11 years when annual precipitations were more than the mean over the past 5 years (7.1 mm). After the flood in 1988, the average annual precipitation decreased significantly, with the mean of being on 358.mm, a 16.% decrease in comparison with the mean over the past 5 years. Meanwhile, large annual and seasonal precipitation variations were both showed in Table 3. The average annual relative humidity (RH) from 1996 to was 59.%, less than that of the past 5 years (6.1%), the RH in spring was the least one of a year (Fig. 5). Table 1 Statistics of annual and seasonal temperature Spring Summer Fall Winter Mean Stdev CV MAX MIN Note: Here Spring represents March, April and May; Summer: June, July and August; Fall: September, October and November; Winter: December and January and February in next year. The following are the same as this. Table Statistics of annual, minimum and maximum temperature Minimum Maximum Mean Stdev CV MAX MIN Table 3 Statistics of annual and seasonal precipitation Spring Summer Fall Winter Mean Stdev CV MAX MIN Table Areas of different Land cover(km ) Water Wetland Cropland Barren temperature( C) Deviation( C) Fig. 1, minimum and maximum average temperature Temperature( C) Fig. Deviations of annual, minimum and maximum average temperature Fig. 3 average temperature in different decades Min Max Min Max

3 8 7 Precipitation(mm) Fig. precipitation Relative humidity(%) Spring Summer Fall Winter Fig. 5 Relative humidity of annual and different seasons Area(km) Water Wetland Crop land Barren Fig. 6 Areas of different land cover classes Land cover dynamics Five years (1979, 1989, 1999, and 1) Landsat images and their land cover dynamics were analyzed. From Figs. 6-9 we can see, crop land area increased from 1979 to 1, water, wetland and barren all showed decreasing trends. Water area in 1979 is the smallest one because of the strong drought in 1977 and Wetlands fragmentation has been worsened. Road, penstock, rice field and other man-made constructions increased.

4 Human activities Since Zhalong Nature Reserve was established, Zhalong wetlands were managed by a special organization - Management Bureau of Zhalong Nature Reserve, which provides some helpful functions on the planning, management, publicizing and protection of the ZNR. Some steps were very important for the preservation of the wetlands. For instance, hunting was forbidden ten years ago; Water citing engineering was actualized since 1, till April, 95 million m 3 has been supplied to ZNR from Nen river by 5 times; The first special water resources plan focused on wetland preservation - Planning Report on Water Resources in Zhalong Wetland was discussed by Songliao Committee in Cangchun city. However, ZNR still faces a lot of threats of some human activities: Since 199, more than 6 reservoirs have been built in the up stream areas for agricultural and other uses, which have resulted in a significant reduction in water supplies from 68 million m 3 per year to million m 3. The population in ZNR is about 9, which is the twice of that in 1979 (Gai, Wang and Wang, ), though a wetland emigration plan started in 3. The project is still on the paper but not been implemented. Until now, 1 construction projects have been suspended within the reserve, therein to the national highway 31 finished in goes across ZNR with 9.km distance and 3m width, which severely blocked the water flow between two sides and brought much noise to the redcrowned cranes and other avifauna (Ding, 5). In September, three man-made dykes with a length of 17-m were dug in the center area of the reserve, which destroyed the structure of wetland formed for hundreds of years (Wang, ). Tens of millions of waste water from industry, agriculture and residence are been drained into the reserve every year (Sun, 1997), the pollution issue has been noticed for more then ten years, but not resolved yet (Zhao,5). ZNR is also the production base of fishery, reed product, agriculture and stockbreeding for Qiqihar City, Lindian and Dumeng County, now.1 million reed product per year can bring $5 economic value. A 556 km filler has appeared in Daqing oil-field, ZNR may supply 1 million m water into the underground (Ding, 5). Discussions For the wetland issues, the major concern is that decisions on management of land areas are made sometimes with a poor understanding of the different wetland characteristics and functions (Lyon, ). Depending on local and regional interests, activities may be designed address specific questions. For example, why have the frequency and intensity of fire in ZNR increased in recent years? The climate change should be the main reason, since the temperature increased significantly over the past years, the precipitation and relative humidity decreased over the past 1 years, there were more and more warm and dry days in a year over the past few decades, which made it easier to trig fires. The other reason should be a lack of water. Regarding the first important factor for the fires-burning the grass on waste land, the farmer s did it every year but just in recent years (1 and 5) the fire frequency and intensity became larger and stronger. Therefore, the climate change enhanced the human and nature damages to the wetland. Some human activity issues such as population, construction, water pollution and production have been existed for a long time but not resolved all along, why? That just divulged the disadvantage of the management system. Does ZNR face threats now? I think so. Although we still can see some good phenomena such as the quantity of redcrowned cranes now () is a little bid better than that of 1996-ten yeas ago (36). The total wetland area did not decrease sharply in recent years, but the total amount of avifauna decreased from 1 thousand to less than 1 thousand. The fish has decreased from 6 to 6 or 7, and the fragmentation was believed to be dominant driving force. The water citing program did have an important role for the Reserve, but it can only keep the red-crowned cranes and other a couple of avifauna being in ZNR. However, considering that the interaction of climate change and human activities could enhance the damage on the wetland, we must do something now to preserve the rare avifauna and also the environment which should be more important for human being. Conclusions The climate in Zhalong Nature Reserve became warmer and drier, the temperature over the past years increased significantly, meanwhile, the precipitation and relative humidity decreased. The cropping area increased, water area decreased, wetland became fragmentation. Human activities including population, construction, water pollution and production have been threatening the wetland ecosystem. The interaction of climate change and human activities further promote human and nature damages to the wetland. We may not do

5 much to climate change, but we can restrict human activities to reduce the threat of climate warming to the minimum. At present, for sustainable development of Zhalong reserve and in order to preserve the nature of the reserve to maintain the biodiversity, an scientific logical feasible integrated management approach should be adopted, which focus on how to resolve the human activities issues of water citing, population, construction, pollution and production, meanwhile, deal with well the conflict between the regional economic development and the preserve of wetland. Acknowledgments This work was supported by NASA on the project-land Use and Land Cover Dynamics of China In Support Of GOFC/GOLD and NEESPI Sciences (NNG5GD9G). We want to thank Jianjun Ge, Shuqing Zhao, Nathan Torbick and Ling Yao in the Center for Global Change and Earth Observations, Michigan State University, for their willingness to help with this paper. References Ding, Y., 5: ZhaLong wetland is a cornucopia. Life Newspaper, China. Gai, H., Wang, S., and Wang, X., : Analysis on ecological environment of Zhalong Wetland. Heilongjiang Environmental Journal, 6, Lyon, J. G., : Wetland landscape characterization. Ann Arbor Press. Sun, H., Wang, L., Wang, Y., Zhao, H., Zhang, S., and Wang, L., 1997: Water pollution and its strategies in Zhalong Nature Reserve, Heilongjiang Geology, 8, Wang, W., Zhao, Y., and Song, X., 6: Water quality assessment in Zhalong wetland, mment.jsp?file=69-86&order=time. Zhao, X., 5: Water environment and sustainable development in Zhalong wetland. Wetland Science, 3, Zou, H., Wu, Q. and Bu, L., 3: Time budget of red-crowned crane during incubating season in Zhalong Nature Reserve after burning and irrigating. Journal of Northeast Forestry University, 31 (6), 1-.